The Scale Shops machines look interesting, but their pictures and descriptions leave something to be desired. Has anyone used them? Do they do the job satisfactorily? I don't get the "one wire" business.
I bought one about ten years ago. It did work, but my impression was that the whole thing was 'amateurish' in execution. It just looked homemade. The copper switch contacts were copper with no special contact area, just bare copper, etc.
I then bought a bunch of German(?) made Lemaco machines and wish I could get about twenty more! The Fulgurex machine is VERY similar though. They were kind of pricey back then, but now... OMG!
I don't remember a one wire concept, but wiring could be really simple by using "steering" diodes, etc. You could throw your panel switch, and the turnout position indicator wouldn't light up until the machine had traveled full stroke.